1. Field of the Invention
Apparatuses and methods consistent with the present invention relate to separating specific components from a sample.
2. Description of the Related Art
Recently, separation of specific components, such as white blood cells (WBCs) from whole blood (WB), has been widely used as a method for diagnosing multiple diseases. Specific components, such as WBCs, can be extracted from a sample, such as blood, by sequentially extracting through chemical procedures components other than the specific components until only the specific components are left, or by separating the sample into a plurality of layers according to components and separating out a specific layer including a great number of the specific components through centrifugation.
FIGS. 1A and 1B are cross-sectional views sequentially illustrating a related art method of separating WBCs from WB through centrifugation.
Referring to FIG. 1A, to extract the WBCs from the WC, 100 μl of a density gradient medium (DGM) 20, which is a reagent, is injected into a tube 10, and a diluted blood solution 22 containing a mixture of 100 μl of WB, 100 μl of salt solution having a concentration of 0.9%, and a small amount of anticoagulant is injected into the tube 10 to be overlaid on the reagent 20. When the tube 10 is centrifuged so that a centrifugal force can be applied in a direction indicated by arrow F, a plurality of layers are formed in the tube 10 according to components due to density difference. A lowermost first layer 31 is a deep red liquid containing a great number of red blood cells (RBCs), a second layer 32 formed on the first layer 31 is a colorless liquid containing a great number of WBCs, and an uppermost third layer 33 is a pale red liquid hardly containing RBCs and WBCs. The second layer 32 containing the WBCs can be manually extracted from the plurality of layers using a pipette 15.
However, the related art method using centrifugation is performed by manually injecting the DGM 20 and the diluted blood solution 22 into the tube 10 and manually extracting the second layer 32 from the tube 10. Accordingly, a sufficient number of WBCs may not be obtained and the WBCs may be contaminated during these operations according to an operator's skill level.